noun
fish even a cat won't eat; unpalatable fish
Colloquial term for fish so unappealing that even a cat would ignore it. Often used humorously or disparagingly.
こんな猫またぎみたいな魚、誰が買うんだ。
Who would buy such a lousy fish that even a cat would turn its nose up at?
彼が釣ってきたのは猫またぎばかりだった。
All he caught were fish that even a cat wouldn't touch.
まずい is a general adjective for 'bad-tasting', while 猫またぎ specifically refers to fish so unappealing that a cat would reject it, carrying a more vivid, colloquial nuance.
Compound of 猫 (cat) and またぎ, the continuative form of またぐ (to step over). Literally 'cat stepping over', implying that even a cat would disdainfully step over such fish rather than eat it.